<!doctype html>
<!-- can not be in a sub-directory as TestContentProvider does not support it -->
<html>
<head><title>running</title></head>
<body><script>
try {
  const worker = new Worker('./worker.js');
  worker.onerror = e => document.title = 'error';
  worker.onmessage = e => document.title = e.data;
  worker.postMessage([]);
} catch (e) {
  document.title = 'exception'
}
</script></body>
</html>
